Efficacy of mycophenolate in preventing relapse of nephrotic syndrome secondary to membranous glomerulonephritis on withdrawal of tacrolimus therapy. This will be initially measured at 6 months post withdrawal of tacrolimus therapy.

The time to obtaining remission from proteinuria The degree of remission of proteinuria obtained (complete or partial) The rate of decline of renal function measured by the Modification of Diet in Renal Disease equation for glomerular filtration rate

change in probability of complete remission (proteinuria < 0.3 g/day) Primary Outcome Measures The primary outcome measure is the change in probability of complete remission (proteinuria < 0.3 g/day) at one year (see Design and power considerations).

Change from baseline in proteinuria

CR (Complete Remission) or PR (Partial Remission: Reduction in UP of > 50% plus final UP ≤ 3.5 g but >0.3g )